package Singleton;

/**
 * @ProjectName: 23种设计模式
 * @Package: Singleton
 * @ClassName: Mgr05
 * @Author: renhan
 * @Description:
 * @Date: 2020/11/10 16:21
 * @Version: 1.0
 *
 *
 * 不能用
 */
public class Mgr05 {
    private static Mgr05 INSTANCE;

    private Mgr05() {
    }

    public static  Mgr05 getInstance() {
        // 会被抢先
        if (INSTANCE == null) {
            synchronized (Mgr05.class) {
                try {
                    Thread.sleep(1);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                INSTANCE = new Mgr05();
            }
        }
        return INSTANCE;
    }

    public void m() {
        System.out.println("m");
    }

    public static void main(String[] args) {
        for (int i = 0; i < 100; i++) {
            new Thread(() -> {
                System.out.println(Mgr05.getInstance().hashCode());
            }).start();
        }
    }
}
